Babies only exist to give access to a stronger pokemon earlier in a weaker form. That and sell plushes.
Only baby that evolved into a usable in-game pokemon is munchlax, who is nigh impossible to obtain this way.
Cross gen evos are great. 75% of the pokemon who received one desperately needed one. Unfortunately only 4 were made available in the base games for no good reason, with 2 being version exclusives.
I don't think there are enough old pokemon that need evolutions to warrant them bringing them back this gen, they would've done it in a past gen if they thought so. Designing evolution lines as they're meant to be in the same generation they're introduced in has been the standard for a while now, and it's more efficient. Komala stands out like a sore thumb though
